This lesson formalizes the concept of leverage, through the idea of mechanical advantage. Unlike the "balance" lesson in A1, this lesson does not seek balance, but the multiplication of force (or distance) through simple machines. Using the lever as the focal point, this lesson gets students to measure the lever arms of a variety of joined-levers (wrenches, pliers, scissors, wire-cutters, etc.). By dividing the input distance by the output distance, they see that a large ratio means a good gripper/cutter.
